Graphophone



June 4, 1929. w, O A 1,715,412

GRAPHOPHONE Filed Nov. 18; 1924 W/D-DOu gZCOG,

WnwEssEs horns or likeamplifiers.

Patented June 4, 1929.

UNITED STATES WILLIAM D. DOUGLAS, 01 ASHEVILLE, NORTH CAROLINA.

GRAPHOPHONE.

Application filed November 18, 1924. SerialNo. 750,553.

This invention relatesto graphophones or talking machines, and; more particularly. .to an improvement therein. which permits. .the usual born or equivalent amplifier tobe eliminated. q

To that end the invention bases its. primary object a simple, practical and. inexpensive construction which includes a more support :or tableon iwhieh -a special sound tube is, carried, the-same being relatively short and thus having its open end relatively close to the jreproducer, thereby having the effect of quicklyreleasingthe-sound and preventing the amplification of foreign sounds,

' and consequently rendering the translation of the composition or record being played clearer and more pleasing to the-sense of hearing. .That is tosay, the invention aims to produce a construction which does away with the ordinary horn or amplifier and thereby eliminates all the harsh, displeasing, tiresome, brassy, and blatant effect common to nearly. alltypes'of machines employing A further object of the invention is to provide a novel sound tube and mounting therefor, the same being made of;- relatively heavy non-resonant material.- 7 3 I With the above and other objeetsjin view which-will more readily: appear-as .the -natizre of the invention is better understood, the same consists in the novel construction, combination and arrangement of partshereinafter more fully described, illustrated andclaimed.

A preferred and practical embodiment of the invention is shown in the accompanying drawings in which:

Figure 1 is a vertical sectional view illus trating the present improvements.

Figure 2 is a side elevation with the to or. cover of the instrument raised.

Figure 3 is a detail sectional view of the sound tube and its mounting.

Figure 4 is a detail section on the line H of F 1g. 3.

Similar reference characters designateeorresponding parts throughout the several figures of the drawings.

As previously indicated, it is one of the primary objects of the present invention to eliminate as far as possible all sound amplifying means which have a tendency to pick up and magnify foreign sounds. Ordinarily graphophones utilize a resonator or amplifier for the sound, the same connecting with a tone arm which carries the reproducer, but in this type of construction the noise of the needle grating against the record material, as well as other noises, are picked up and magnlfied in the rendition .of a selection thereby frequently marring otherwise good renditions of solos or other selections being played. Accordingly, .it is proposed to utilize a simple construction that. entirely eliminates horn ..or'other amplifier, and which may be used withor. Without aeover as desired, although .s uch cover may be desirable for more or less ornamental effect and .as a protection to the reproducing or translating parts of the apparatus as will presentlyappear.

In the embodiment of the imentionshown in the drawings the same includes a support designated generally as l, thesamc being adapted to be mounted or carried upon standards 2 or their equivalent. In that connection it may be pointed out thatthe supportl may be suspended from above instead of supportedg :froin. :beneatlnflivithout afi'ecting the efficiency of the apparatus. .The said support Iprefer bly, carries a. motor. containing compartment or -bo X designated generally asM and having the usual mechanism for operating japlaten-3 foi 'supportinga record R. 'At'a suitable and convenient location on the support 1 there is'mou nted the novel sound tube designated generally as S, the same being of flaring formationat one end and the remaining part'or body being cylindrical, that is, straight and of uniform diameter to the sound discharge month there of. The reprodueer 4 is carried by the small end of the flaring part of the tube body and the opposite end 5 provides a sound releasing mouth above the surface ofthe platform or support 1. The body of thetube S may be supported at an intermediate point by a substantiallyv U-shaped bracket 6 provided with ,a swivel-post-Gtfor fitting into and resting upon the ball bearing 6 in the bottom of the socket of a standard 7 mountedon the support 1. These ball bearings prevent vibration and also make an anti-friction support for the post ofthe bracket. Thus, the said tube S may have a universal movement due to the fact that it is pivotally supported in the bracket 6 and rotatably supported in the standard or post 7.

The said sound tube S is preferably made of aluminum, and the Walls thereof are made relatively thick as indicated in Figure 1, and for the purpose of counter-balancing the otal support of the tube in the bracket'ti, as.

conditions may require by releasing and tightening the set screw. Furthermore, the tightening of the set screw 9 to. secure the ring to the tube has the effect of damping or preventing the vibration of the sound tube,

thereby avoiding the reproduction of 'foreign sounds. l

The support 1 may be provided at one side thereof with a cover designated generally as C, and if desired the said cover may be'provided in its top wall with the control slats or shutters 10. which may be manipulated by the single knob 11. As previously indicated the said cover may or may not be used with the device but when it is used as shown in Figure 1, it may constitute a mufiicr for the sound emanating from the mouth 5 of the tube S, or when raised as in Figure 2 may act as an acoustical receiver and deflector for directing the sound toward the open ,side of the apparatus.

With the device in the position shown in Figure 2 it will be apparent that since the sound tube opens into the uplifted cover, a very pleasing acoustical effect may be obtained, this result being due to the fact that the sound tube discharges into an enclosure which is not connected with the sound tube as is usually the case in the cabinet type. of talking machines.

In connection with the mounting of the sound tube S in the bracket 6 it may be noted that the bottom of the bracket 6 may be pro vided with a cushion 6 of rubber, felt or like material which will prevent metal to metal contact between the sound tube and the brackct when the tube is lifted or dropped to one side of the platen.

Also, the tube may be provided with one or more filters F and F for example, made of absorbent cotton and respectively located near the reproducer and mouth of the tube.

By the use of the present sound tube great clarity of reproduction and also considerable carrying power for the sound is obtained. It is well known that soundtravels in the form of waves, each of which is composed of a number of nodes, and assumed to be in the form of a disk having its opposite side surfaces corrugated to define the peaks of the nodes. If not disturbed by outside forces the nodes remain uniformly concentric with relation to the center of the wave, and if the waves are controlled in such a manner as to be released without distortion or obstruction, superior rcproduction of the sounds will result. By the use of the present sound tube the sound waves are gradually allowed to expand in the flaring portion of the body and then as they pass along the straight or cylindrical part thereof they are controlled or guided in such a way that they are released without distortion from their normal circular shape, thereby producing erfect release of the sound Waves which are ree'from noisy effects.

Substantially one half of the length of the sound tube S is of flaring formation while the other half is of uniform diameter toward the open discharge mouth, and the axis of the body of the tube which includes the flaring and cyl indrical portions is straight. only a small curved portion at one end being necessary to accommodate the sound box or reproducer. Without further description it is thought that the features and advantages of the invention will be readily apparent to those skilled in the art, audit will of course be understood that changes in the form, propor tion and minor details of construct-ion may be resorted to, without departing from the spirit of the 'invention and scope of the appended claims.

I claim:

1. In a graphophone, a supporting table, a rotary platen, a sound tube comprising a thick walled hollow body having a tapering interior surface merging into a cylindrical surface leading to an open discharge mouth. a post carried by the table adjacent the platen, a swivelled supporting bracket carried by the post and engaging the tube nearer its mouth than the end opposite its mouth, a reproducer connected to the end of the body having the tapering interior, and a ring member adjustably mounted on the outside of the thick walled body near its mouth to counter-balance the weight of the body and the reproducer at one side of the bracket.

2. A sound tube for graphophones. com prising a hollow body having walls of relatively thick metal, said body having a short tapering interior surface merging into a. longer cylindrical surface extending into the open discharge end of the body and both the ta pe r ing and cylindrical surfaces being clear of obstructions, a reproducer adapted to he carried by the end having the short tapering interior surface, a support for said sound tube, and a combined counter-balance ring and vibration damping member adjustably fitted to the thick walled body adjacent to the open end thereof.

In testimony whereof I hereunto aflix my signature.

WILLIAM D. DOUGLAS. 

